[Feature] Allow list of AlloType as dtype for Structure

[rlin10]

Is your feature request related to a problem? Please describe.
Yes. Currently, Allo's Structure type asserts if the dtype input is of AlloType. This causes the scenario where if the input type is a list such as uint8[16], there is an assertion failure.

Something like this works

t = Structure({
    "uint": uint8
})

but the following doesn't

t1 = Structure({
    "uint list": uint8[16]
})

Describe the solution you'd like
List of AlloType should also be allowed as dtype when creating a type using Structure